There has been a national investment of $635 million dollars to support early intervention efforts for infants and toddlers through the Early Head Start (EHS)-Child Care partnerships and expansion grants. EHS focuses on sustainable intervention efforts to support families in their role as children's first teachers. As one of the earliest prevention and intervention programs for low-income children and families, Early Head Start (EHS) incorporates a comprehensive whole child and two-generational approach that acknowledges the foundational role that parents play in their children's early learning and social-emotional development (Sheridan, Marvin, Knoche, & Edwards, 2008). As part of this national initiative, three local Miami-Dade community agencies (Miami-Dade County/Monroe Early Learning Coalition, Miami Dade County Action and Human Services Department; The United Way of Miami-Dade County) were funded to implement high-quality Early Head Start center-based programs. These agencies have identified engaging families as a top priority, yet there are no validated measures that capture multiple dimensions of family engagement for toddlers enrolled in center-based programs. In fact, most measures focus on tracking the number of family participation hours, rather than collecting meaningful measures that will help support family engagement intervention efforts implemented by Early Head Start programs. This dissertation project will develop a family engagement measure in partnership with EHS staff and families that is appropriate for use with ethnically diverse families of toddlers enrolled in center-based programs. The project has the following objectives: (1) To gain an understanding of family engagement from the perspective of EHS family support staff, teachers, and ethnically diverse families of toddlers (2) To develop and obtain construct validity evidence for a measure of family engagement that is relevant for ethnically diverse Early Head Start families of toddlers (3) To investigate the concurrent validity of the family engagement measure by examining its relationship with other family engagement measures, children's social emotional skills, and language outcomes and (4) To investigate the practical utility of the family engagement measure in informing appropriate and effective family intervention efforts in the Early Head Start programs. This project will result in the first validated measure of family engagement available for ethnically diverse families of toddlers in center-based programs. Additionally, practical ways to use the measure and share results with teachers and families will be co-constructed with EHS programs. This will facilitate program administrators' use of the newly developed measure for implementation and continuous improvement of family intervention efforts.